The present invention relates generally to electrical protection, and in particular, to electrical protection circuitry for a docking station base of a hand held meter, such as for example a blood glucose meter, which prevents system damage from liquid contact and unspecified power supply voltages and currents, and the method thereof.
In hospitals and out-patient settings that desire to monitor and maintain a patient physiological values, there are a variety of hand held meters involved in bedside testing or near patient testing, which record and transmit such patient data to a remote health information system. One such hand held meter is a blood glucose meter, which in one prior art device, the transmission of patient data between the meter and the remote health information system is via a docking station base. In such a prior art device, the docking station base, in addition to providing a data connection to the information system, also provides power to recharge the battery of the meter. To connect the meter to the base, the meter is seated or docked in a cradle portion of the base having at the bottom thereof a meter interface connector. The meter interface connector provides both the power and data connections to the meter from the base.
Due to the use of such hand held meters in the near patient testing setting, customer usage includes periodic cleaning and disinfecting of the exterior surfaces of the meter and base. As the meter and base are not intended to be submerged in any liquid, the recommended cleaning process includes spraying a cloth with a cleaning solution and wiping down the meter and base with the dampened cloth. However, the problem induced to the combined meter and base system is that occasionally customers either clean the meter and base with an over-saturated cloth, or spray the meter and base directly with the cleaning solution which can result in significant residual cleaning solution being left on the meter and base. The excess solution, through help from gravity, collects in the cradle portion of the base or wicks down through the meter interface connector.
In such a prior art docking station base, if significant enough solution collects in the base, the cleaning solution can drain inside the base housing in and around the power and data connector and onto a printed circuit board enclosed therein. Once inside the housing, the cleaning solution (specifically bleach based products) can form dendrites on the wiring assembly of the printed circuit board which overtime, can eventually result in unit failure. In some cases, meter and/or base failure occurs almost immediately after solution application and docking of the meter to the base. In other cases, failure of the base is progressive, causing power fluctuations from an electrical short or other compromised circuitry which may unnoticeably jeopardize the operation of the meter. None of the prior art hand held meters having a docking station base addresses the problems of non-recommended cleaning practices and the application of unspecified power supply voltages and currents that may result therefrom.